BARABOO (AP) – The Wisconsin Department of Justice has requested that a 63-year-old man convicted of second-degree murder and two sexual assault charges be committed for treatment.

A petition filed Friday under the state’s sexual predator law says Herbert Droste is a sexually violent person, the Baraboo News Republic reported. He was sentenced to 20 years in prison for the second-degree murder and sexual assault of 17-year-old Sandra Bressler in 1981. He was also sentenced to 15 years for first-degree sexual assault.

Droste served 16 years before he was released on parole in March 1997. The state tried to keep Droste in prison because authorities said he was linked to other sexual assaults. But a judge ruled that the state didn’t successfully prove that he qualified to be held under the sexual predator law.

Droste’s parole was revoked in December 1997 after he made a bomb threat, threatened a parole agent and planned to escape and kill a parole agent.

Under Wisconsin law, a person who has been convicted of a sexually violent offense and is dangerous to others because of a mental illness can be committed to the custody and care of the Department of Health Services for treatment until the person is no longer considered sexually violent.

The state’s petition says Droste is predisposed to commit acts of sexual violence because of a mental illness. He will be subject to civil commitment for treatment if the state proves he is a sexually violent person.

Droste was scheduled to be released from the Department of Corrections on Tuesday. He will be detained at a Department of Health Services facility to await a probable cause hearing scheduled for the end of August.